Backtracking
Subsets II
You are given an array nums of integers, which may contain duplicates. Return all possible subsets.
Example 1:
public List<List<Integer>> subsetsWithDup(int[] nums) {
List<List<Integer>> res = new ArrayList<>();
Arrays.sort(nums);
backtrack(0, new ArrayList<>(), nums, res);
return res;
}
private void backtrack(int start, List<Integer> subset, int[] nums, List<List<Integer>> res) {
res.add(new ArrayList<>(subset));
for (int i = start; i < nums.length; i++) {
if (i > start && nums[i] == nums[i - 1]) {
continue;
}
subset.add(nums[i]);
backtrack(i + 1, subset, nums, res);
subset.remove(subset.size() - 1);
}
}
